**No Level 4 CDC Travel Health Notice appears imminent by year-end, supporting the 75% market-implied probability.** CDC Level 4 notices, which advise avoiding all travel due to extreme health risks with no effective precautions, remain unused as of mid-June 2026. Current notices top out at Level 2 for circulating poliovirus (updated March 2026 to include Laos and Namibia) and select Level 1 alerts for dengue, chikungunya, hepatitis A, and global measles. These reflect ongoing but contained transmission patterns monitored by CDC surveillance, without the uncontrolled outbreaks or novel pathogens that historically trigger Level 4 status, such as peak COVID-19 surges. No recent model runs, case thresholds, or official CDC/NOAA-style escalations point to conditions that would meet Level 4 criteria—extreme risk without mitigation options—before December 31. Traders appear to weigh the low baseline likelihood of rapid escalation against routine seasonal and endemic activity, with upcoming surveillance updates unlikely to shift this assessment absent a major emergence.